ANALYSIS OF MEDICATION PRESCRIPTION IN AN ARGENTINIAN GERIATRIC HOSPITAL Background: Although polypharmacy may be justified in elderly patients with multiple diseases, it may be dangerous, especially when it includes potentially inappropriate medications (PIM). Aim: To identify inappropriate medication and factors associated with the most relevant prescriptions among older people. Material and methods: Cross-sectional observational analysis of drugs prescribed during the first trimester of 2010 to 179 older adults aged 77 ± 8 years (98 women), living in a geriatric reference hospital in Argentina. The use of potentially inappropriate medications (PIM) in elderly patients was analyzed using Beers Criteria updated to 2012. Results: The mean number of drugs prescribed per individual was 6.1 ± 2.7. The most commonly used drugs were anti-ulcer agents (58.1%), agents acting on the renin-angiotensin system (54.2%), antithrombotic medications (50.8%) and benzodiazepines (50.8 %). The use of antacids and anti-ulcer agents, psychotropic drugs and PIM was significantly higher among patients using six or more drugs daily, compared to the less medicated group (odds ratio (OR) = 6.8, 95% confidence intervals (CI) 3.5-13.2; OR=15.0, 95%CI 5.9-38.4; OR=5.0; 95%IC 2.6-9.8, respectively). Thirty one percent of participants using non-steroidal anti-inflammatory drugs, were not receiving medications for gastric protection. One to four drugs included in the Beers list were prescribed to 66% of participants. Conclusions: Despite the high prevalence of use of antacids and anti-ulcer agents, these drugs were not prescribed to a significant proportion of patients using non-steroidal anti-inflammatory drugs.  Strategies to optimize pharmacotherapy in the elderly population are urgently required.